1. Field of the Invention
This invention relates generally to massaging apparatuses and, more specifically, to a massaging apparatus which is installed in the back rest of a chair or in a bed and adapted to massage desired parts of the human body supported thereon.
2. Description to the Prior Art
Massaging machines adapted to massage parts of the human body supported on the back rest of a chair or on a bed by means of a pair of massaging wheels driven for rotation have already been known, as disclosed in U.S. Pat. Nos. 3,633,571 issued Jan. 11, 1972 and 4,167,182 issued Sept. 11, 1979. U.S. Pat. No. 3,633,571 discloses a massaging machine having a pair of massaging wheels attached to a main shaft in inclined relation thereto. In such massaging machine, the rotation of the main shaft and hence the massaging wheels by a motor provides the same massaging effect on the human body as that provided by a masseur. In this patent, the spacing between the pair of massaging wheel is variable. Thus, by changing the spacing, the massaging wheels can be positioned on widthwise spaced desired parts of the human body. Likewise, U.S. Pat. No. 4,167,182 discloses a massaging apparatus having a pair of massaging wheels attached to a main shaft. In this U.S. Patent, the pair of massaging wheels are shiftable, e.g., in the direction of the length of a chair, i.e, vertically so that they may be brought to an optimum position on the human body. Thus, massaging apparatuses adapted to adjust the spacing or vertical position of a pair of massaging wheels have already been proposed.
Further, a massaging apparatus adapted to adjust both the vertical position and spacing of a pair of massaging wheels has already been put into practical use. In such conventional massaging apparatuses, however, their operations are very complex or troublesome. More specifically, the conventional massaging apparatus is provided with separate operating means, i.e., a means for vertically moving the massaging wheels and a means for adjusting the spacing of the massaging wheels. For example, when it is desired to massage the shoulders, the operating means for vertical movement is first manipulated to bring the massaging wheels to the level of the shoulders and then the other operating means is manipulated to suitably increase the massaging wheel spacing. Thus, with the conventional massaging apparatus, when it is desired to bring the massaging wheels to a desired position on the human body, it has been necessary to manipulate the two operating means so as to position the massaging wheels. Further, since the massaging wheels are eccentrically attached to the main shaft, the massaging effect attainable differs with the direction of rotation of the massaging wheels. For example, the satisfactory direction of rotation for massaging the shoulders is opposite to that for the waist. In the conventional massaging apparatus, therefore, to obtain the best massaging effect, it has been necessary to determine and select the required direction of rotation of the massaging wheels. Thus, there has been a drawback that because of the complex operation required, it is impossible for general users, particularly elderly persons, to make effective use of the overall function of the massaging machine or, even if such is possible, it is very difficult for them to understand how to operate the massaging machine.